The AEC's main responsibility is to conduct federal elections, by-elections and referendums. The AEC is also responsible for seat boundaries and redistributions, and the maintenance of an up-to-date electoral roll. Under the Joint Roll Arrangements, the AEC maintains the electoral roll for the whole of Australia, which is used by the state and territory Electoral Commissions to conduct their elections. The AEC publishes detailed election results and follows up electors who fail to vote

The AEC is also responsible for monitoring the activities of registered political parties, including receiving returns from parties of donations and expenditures, and the publication of the information. The AEC also plays an electoral education role, aiming to educate citizens about the electoral process by which representatives are elected, and by which the Australian Constitution is changed (referendums). It also plays a role in industrial voting (e.g., votes on industrial action).

Political parties in Australia are publicly funded by the AEC, to reduce the influence of private money upon elections, and subsequently, the influence of private money upon the shaping of public policy. After each election, the AEC distributes a set amount of money to each political party, per vote received. For example, after the 2013 election, political parties and candidates received $58.1 million in election funding. The Liberal Party received $23.9 million in public funds, as part of the Coalition total of $27.2 million, while the Labor Party received $20.8 million.[2]

The AEC is answerable to the Joint Standing Committee on Electoral Matters[4] of the Parliament of Australia, and must report on how elections were carried out and the success of elections in general.

The AEC was created by and operates under the Commonwealth Electoral Act 1918. It consists of a chairman (a Judge or a retired Judge of the Federal Court), the Electoral Commissioner and a non-judicial member (usually the Australian Statistician). The Electoral Commissioner has the powers of a Secretary of a Department under the Public Service Act 1999 and the Financial Management and Accountability Act 1998. The Chairperson and the third, non-judicial member both hold their offices on a part-time basis.

In Australia voter registration is called "enrolment", and the electoral register is called an "electoral roll". A permanent Australian federal electoral roll has been maintained since 1908, and enrolment has been compulsory for federal elections since 1912. The AEC maintains Australia's federal electoral roll, which is used for federal elections and referendums. Each state also has its own electoral commission or office, but voters need to register only with the AEC which shares the registration details with the relevant state electoral commission, except in the case of Western Australia, which maintains its own electoral roll. The federal roll also forms the basis of state (except in Western Australia) and local electoral rolls.[7]

AEC registration covers federal, state and local voter registration. In Australia and in each state and territory, it is a legal offence to fail to vote (or, at the very least, attend a polling station and have one's name crossed off the roll) at any federal or state election, punishable by a nominal fine. The amount varies between federal and state elections. (The fine for not voting is currently A$75.00 in Victoria. This figure is indexed at the beginning of every financial year.) Usually people are issued with warnings when it is found that they have not voted, and they are given an opportunity to show cause. Acceptable reasons for not voting may include being in the accident department of a hospital, being ill (requires confirmation), being out of the country on election day, religious objections, being incarcerated, etc. "I forgot" is not considered acceptable and will incur a fine. Section 245 of the Electoral Act (Cwth) provides that if an elector has been asked the "true reason" for his failure to vote states that he did not do so because it was against his religion, this statement shall be regarded as conclusive, and no further action will be taken.

Traditionally, voters cannot register within three weeks of an election. In 2004 the Howard government passed legislation that prevented registration after 8 pm on the day that the writs were issued (this can be up to 10 days after the election has been announced).[8] This legislation was considered controversial by some Australians who contended it disenfranchised first-time voters or those who have forgotten to update their enrolment. The law was repealed just before the 2010 federal election, after advocacy group GetUp! obtained a High Court ruling[9] that the changes were unconstitutional.[10] 16 and 17 year olds can provisionally enrol and are able to vote when they turn 18.[11]